201003905 六、發明說明： 【發明所屬之技術領域】 本發明大體關於影像感應器，具體而言但不限於，關於 前照式影像感應器。 【先前技術】 積體電路已被研發以減少用於實施電路系統之元件的尺 寸。舉例來說，積體電路使用越來越小的設計特徵，其將 減小用於實施該電路系統之面積，使得現在設計特徵遠小 於可見光之波長。利用影像感應器之越來越小的尺寸及為 一感應陣列之部分的單獨像素，重要的係更有效地抓取當 入射光照射該感應陣列時形成的電荷。因此，更有效地抓 取光子產生的電荷有助於維持或改善被尺寸越來越小之感 應陣列所抓取之電子影像之品質。 【實施方式】 本文描述-種具有背面鈍化及金屬層之影像感應器的實施 2在如下之描述中將提到—些具體細節以徹底理解該等 實施例。然而’相關技術熟練者將瞭解描述於此之該等技 :二有個或更多個該等具體細節的情況下實施， :二其他方法、元件、材料等而實施。纟其他情況中， 些態^^或描述熟知之結構、材料或操作以避免混清某 對 個實施例」或「一實施例 頁穿此說明書 述意為聯繫該實施例;…例」之< 包含於本發明之至少一個實二二-結構或特性: ““列中。因&，在貫穿此說 140690.doc 201003905 曰的夕個地方出現的語句「在一個實施例中」或「在一實 方包{列中 ^ 」 + ~定全都涉及同一個實施例。此外，該等特 寺徵、’α構或特性可以任何適當方式組合於一個或更多 個只％例中。使用於此之用語「或」通常意為一種涵蓋一 包含性功能（諸如「及/或」）的意思。 此况明書中使用—些技術術語。這些術語採用其在其所 來自之忒技術中的普通意義，除非在文中被明確地界定或201003905 VI. Description of the Invention: TECHNICAL FIELD OF THE INVENTION The present invention generally relates to image sensors, and more particularly, but not exclusively, to front-illuminated image sensors. [Prior Art] Integrated circuits have been developed to reduce the size of components used to implement the circuit system. For example, integrated circuits use increasingly smaller design features that will reduce the area used to implement the circuitry such that the design features are now much smaller than the wavelength of visible light. Utilizing the increasingly smaller size of the image sensor and the individual pixels that are part of a sensing array, it is important to more effectively capture the charge that is formed when the incident light illuminates the sensing array. Therefore, more efficient capture of the charge generated by the photons helps maintain or improve the quality of the electronic image captured by the increasingly smaller size sensor array. [Embodiment] Described herein is an implementation of an image sensor having a backside passivation and a metal layer. 2 In the following description, specific details are set forth to provide a thorough understanding of the embodiments. However, it will be understood by those skilled in the art that the present invention may be practiced in the context of one or more of the specific details. In other instances, some structures or materials are described to avoid obscuring a certain embodiment or "an embodiment of this specification is intended to be in connection with the embodiment; Included in at least one real two-two structure or property of the invention: "in the column. The statement "in one embodiment" or "in a real package {column ^" + ~ refers to the same embodiment, which occurs in the same place as the & Moreover, the features, 'alpha configurations or characteristics may be combined in one or more of the only examples in any suitable manner. The term "or" as used herein generally means to encompass an inclusive function such as "and/or". Some technical terms are used in this book. These terms take the ordinary meaning of the technology from which they are derived, unless explicitly defined in the text or
其使用背景明確提議。「量子效率」纟此被界定為被產生 =載子的數里與入射於一影像感應器之一有源區域之上之 二子之數里的比率。「暗電流」在此被界定為在沒有入射 光$ 一影像感應器中流動的電流。「白像素缺陷」在此被 界疋為-影像感應器中包含一具有一過量漏電流之有源區 域的像素。 圖1係一根據本發明之一實施例之一影像感應器i 〇〇的方 塊圖。所顯示之影像感應器1⑻之實施例包含-像素陣列 105、續出電路系統110、功能邏輯115及控制電路系統 像素陣列丨〇5為—二維（「2D」）的影像感應器或像素（例 、像素PI P2···、pn)陣列。在—個實施例中，各個像素 為一主動像素感應器（「APS」），例如一種互補型金屬·氧 化物-半導體（「CM0S」）影像像素。如圖所示，各個像素 被配置於-列（例如列R_y)及—行（例如行叫叫以獲 取一人物、地點或物體之影像資料，然後該資料可被㈣ 表現該人物、地點或物體之一 2D影像。 140690.doc 201003905 在各個像素獲得其影像資 被讀出電路系統no讀出並傳逆至何後，該影像資料 系統η。可包含放大… 功能邏輯115。讀出電路 路系統、類比_ 其他。邏輯功能115可僅儲存兮旦/游一 、私路系統或 影像效果"丨 "衫像貧料或藉由應用後期 像放果(例如寶裁、旋轉、移除紅眼、_产' 對比度或其他）而操控該影像 儿又、调整 山； 冢貝枓。在一個實施例中，4 =系統U。可沿著讀出行線(已顯示)同時讀出—列影： 貝枓或可利用許多其他技術（未顯示）讀出該影m 如連續讀出或同時完全平行讀出所有像素。 控制電路系統120被耗合至像素陣列ι〇5以控制像素陣列 105之操作特性。舉例來說，控制電路系統㈣可產生—快 門信號以控制影像採集。 、 圖2為一種前照式影像感應器之一成像像素2〇〇之一截面 圖。成像像素200為顯示於圖！中之像素陣列J 〇5之至少一 個像素的可行實施。成像像素2〇〇之該被顯示之實施^包 含一半導體層（即P型基板205)。基板205中形成有一光電 一極體（即N區域210)、一 P+釘紮層215、一 p+植入層22〇、 一淺溝渠隔離（「STI」）225、一傳送閘極23〇及一浮動擴散 (即N+區域23 5)。為便於顯示某些特徵，該圖式不必按比 例續'製。 成像像素200對入射於基板205之前表面207的光具有光 敏性。在成像像素200中’大部分的光子吸收作用發生於 基板205之背面209附近。為分離由光子吸收作用產生的該 等電子-電洞對並將電子驅動至N·區域210，一靠近基板 140690.doc 201003905 205之背面209的電場被使用。因此藉由摻雜基板2〇5之該 背面209可產生一高度摻雜的p+植入層220藉以產生此電 場。在一個實施例中’ P +植入層22〇可利用硼植入及雷射 退火產生。 如圖2所示’一 p+植入層被植入至一植入深度2丨丨，使得 有一剩餘基板厚度213。總體而言，較大的剩餘厚度可提 南該像素對較長波長的敏感性’並增加串擾（導致敏感性 下降）。 在被顯示之實施例中，植入深度21丨代表從背面2〇9測量 的P+植入層延伸至基板205中的距離。剩餘基板厚度213代 表從植入深度211至前表面207的距離。根據揭示於此之該 等實施例，植入深度211、P+植入層220之離子濃度及/或剩 餘基板厚度213可被選擇以提高（例如優化）成像像素2〇〇之 光邊及總體性能。舉例來說，藉由細心選擇植入深度 211、離子濃度及/或剩餘基板厚度213，成像像素200之量 子效率及光谱性能可被提南。此外，亦可減弱暗電流。 在一個實施例中，P+植入層220係一高摻雜硼植入層。 該硼摻雜層可具有一被選擇以提高成像像素2〇〇之量子效 率的硼離子濃度。該硼植入層亦可具有一被選擇以減弱暗 電流的硼離子濃度。在一個實施例中，硼植入層可具有一 分級的硼離子濃度’其中背面209附近之硼離子濃度高於 在植入深度2 11附近的離子濃度。舉例來說，p+植入層2 2 〇 在背面209附近可具有一在大約3乂10〗7離子/(；1113到5)<1〇19離 子/cm3範圍内的硼離子濃度，而在植入深度2丨丨附近之硼 140690.doc 201003905 離子；辰度可在大約1 x 1 014離子/cm3到3 χ 1 〇15離子/cm3範圍 内。在一個實施例中，p+植入層22〇之硼植入可利用氟化 硼（BF2)作為摻雜劑或利用乙硼烷⑺汨6)作為摻雜劑源而被 實施。 如上面所提到，植入深度211亦可被選擇以便提高量子 =率、提高對紅色波長及近汛波長之敏感度及減弱暗電 流。在一個實施例中，從P +層22〇之背面測量植入深度211 在大約】00 n„^〗 400 nm之範園内。p+層22〇被用於鈍化成 像像素200之p型基板2〇5之背側（用於金屬層Μ]之製備， 該金屬層原本趨向於捕獲被釋放之電子）。（金屬層222亦可 由石夕化物或其他合適的反射材料構成。） 在一個實施例中，剩餘基板厚度213可具有較佳的值。 ^如，剩餘基板厚度213及p+層22〇之一總和可為大約卜4 U米 不例性值為3微米。剩餘基板厚度2 13亦可被選擇 使得金屬層222被用於主要反射光之紅色（或更長的）波長。 口此形成於6亥半導體層之背面的該金屬層可被用於主要 向該N-區域反射具有更長波長的光子。金屬層222之金屬 深度215—般可為任何適於反射光的厚度。 有色光射線R、GAB分別顯示紅色波長、綠色波長及藍 色波長的光。該剩餘基板厚度被選擇使得藍色及綠色光在 該基板中的穿透深度大體不如更長波長之光。因此剩餘基 板厚度213可被遠擇使得該基板之厚度吸收大部分具有更 短波長的光子(例如超過-半的波長短於紅色波長之光子 被吸收），同時一更大t卜彳丨 的/、有更長波長之光子不被吸 140690.doc 201003905Its background of use is clearly proposed. "Quantum efficiency" is defined as the ratio of the number of generated subcarriers to the number of two sub-objects incident on one of the active regions of an image sensor. "Dark current" is defined herein as the current flowing in an image sensor without incident light. The "white pixel defect" is hereby defined as a pixel containing an active area having an excessive leakage current in the image sensor. 1 is a block diagram of an image sensor i 根据 in accordance with an embodiment of the present invention. The embodiment of the displayed image sensor 1 (8) includes a pixel array 105, a continuous circuit system 110, a function logic 115, and a control circuit system pixel array 丨〇5 as a two-dimensional ("2D") image sensor or pixel ( Example, pixel PI P2···, pn) array. In one embodiment, each pixel is an active pixel sensor ("APS"), such as a complementary metal oxide-semiconductor ("CMOS") image pixel. As shown, each pixel is configured in a column (eg, column R_y) and a row (eg, a row is called to obtain image data of a person, place, or object, and then the material can be represented by (4) the person, place, or object. A 2D image. 140690.doc 201003905 After each pixel obtains its image resource readout circuitry no read and reversed, the image data system η can include amplification... Function Logic 115. Readout Circuit System , analogy _ other. Logic function 115 can only store 兮 / / swim one, private system or image effect " 丨 quot quot 或 或 或 或 或 或 或 或 或 或 或 或 或 或 或 或 或 或 或 或 或 或 或 或 或 或 或 或 或 或 或 或 或 或 或, ‘production' contrast or other) while manipulating the image, adjusting the mountain; 冢贝枓. In one embodiment, 4 = system U. can be read simultaneously along the readout line (shown) - column: Bellow may use a number of other techniques (not shown) to read the shadow m as continuously read or simultaneously read all pixels in parallel. Control circuitry 120 is consuming the pixel array ι〇5 to control the operation of pixel array 105. Characteristics. Examples Said control circuit system (4) can generate - shutter signal to control image acquisition. Figure 2 is a cross-sectional view of one of the imaging pixels 2 of a front-illuminated image sensor. Imaging pixel 200 is the pixel shown in Figure! A possible implementation of at least one pixel of the array J. The imaging pixel 2 is shown to comprise a semiconductor layer (ie, a P-type substrate 205). A photodiode is formed in the substrate 205 (ie, the N region 210) ), a P+ pinning layer 215, a p+ implant layer 22〇, a shallow trench isolation (“STI”) 225, a transfer gate 23〇, and a floating diffusion (ie, N+ region 23 5). The features are not necessarily to scale. The imaging pixel 200 is photosensitive to light incident on the front surface 207 of the substrate 205. In the imaging pixel 200, most of the photon absorption occurs near the back surface 209 of the substrate 205. To separate the pairs of electron-holes generated by photon absorption and drive electrons to the N·region 210, an electric field close to the back surface 209 of the substrate 140690.doc 201003905 205 is used. Thus by doping the substrate 2〇 5 of the back 209 can produce a highly doped p+ implant layer 220 to generate this electric field. In one embodiment, the 'P+ implant layer 22 can be produced using boron implantation and laser annealing. As shown in Figure 2, a p+ The implant layer is implanted to an implant depth of 2 丨丨 such that there is a residual substrate thickness 213. In general, a larger residual thickness can increase the sensitivity of the pixel to longer wavelengths and increase crosstalk (resulting in sensitivity) Sexual decline.) In the embodiment shown, the implant depth 21 丨 represents the distance that extends from the back side 2〇9 of the P+ implant layer into the substrate 205. The remaining substrate thickness 213 represents the distance from the implant depth 211 to the front surface 207. According to such embodiments disclosed herein, the implantation depth 211, the ion concentration of the P+ implant layer 220, and/or the remaining substrate thickness 213 can be selected to enhance (e.g., optimize) the edge and overall performance of the imaging pixel 2 . For example, by careful selection of implantation depth 211, ion concentration, and/or residual substrate thickness 213, the quantum efficiency and spectral performance of imaging pixel 200 can be advanced. In addition, dark current can be attenuated. In one embodiment, the P+ implant layer 220 is a highly doped boron implant layer. The boron doped layer can have a boron ion concentration selected to increase the quantum efficiency of the imaging pixel 2〇〇. The boron implant layer can also have a boron ion concentration selected to attenuate dark current. In one embodiment, the boron implant layer can have a graded boron ion concentration' wherein the boron ion concentration near the back side 209 is higher than the ion concentration near the implant depth 211. For example, the p+ implant layer 2 2 〇 may have a boron ion concentration in the range of about 3 乂 10 7 7 ions / (; 1113 to 5) < 1 〇 19 ions / cm 3 in the vicinity of the back surface 209, and Boron near the depth of 2丨丨 Boron 140690.doc 201003905 ion; the length can be in the range of about 1 x 1 014 ions / cm3 to 3 χ 1 〇 15 ions / cm3. In one embodiment, boron implantation of the p+ implant layer 22 can be carried out using boron fluoride (BF2) as a dopant or diborane (7) 汨6) as a dopant source. As mentioned above, the implant depth 211 can also be selected to increase the quantum = rate, increase sensitivity to red and near wavelengths, and attenuate dark current. In one embodiment, the implant depth 211 is measured from the back side of the P+ layer 22〇 in a range of approximately 00 n°^400 nm. The p+ layer 22〇 is used to passivate the p-type substrate 2 of the imaging pixel 200. The preparation of the back side of 5 (for metal layer germanium), which tends to capture the released electrons. (The metal layer 222 may also be composed of a lithiated or other suitable reflective material.) In one embodiment The remaining substrate thickness 213 may have a preferable value. For example, the sum of the remaining substrate thickness 213 and the p+ layer 22〇 may be about 4 U meters, and the non-representative value is 3 μm. The remaining substrate thickness 2 13 may also be The metal layer 222 is selected such that the red (or longer) wavelength of the primary reflected light is used. The metal layer formed on the back side of the 6-well semiconductor layer can be used to mainly reflect to the N-region with a longer wavelength. The photon 215 of the metal layer 222 can generally be any thickness suitable for reflecting light. The colored light rays R, GAB respectively display red, green and blue wavelengths. The remaining substrate thickness is selected such that blue Color and green light in the substrate The penetration depth is generally inferior to that of longer wavelengths. Thus the remaining substrate thickness 213 can be chosen such that the thickness of the substrate absorbs most of the photons with shorter wavelengths (eg, more than - half wavelengths are shorter than the red wavelength photons are absorbed) At the same time, a larger t-dipole/, photon with a longer wavelength is not absorbed. 140690.doc 201003905
收。如上所述，剩餘基板厚度213亦可被選擇使得金屬層 222被用於主要反射紅色（及更長）波長之光（例如超過5〇0/〇 的被金屬層222反射之光子具有紅色或更長波長）。因此， 該像素對光的紅色（或更長之）波長之敏感度可藉由提供金 屬層222而被改善’該金屬層將更長之波長反射回到該前 表面207，附加電子電洞對可被產生於此處（N-區域21〇可 捕獲該等被釋放之電子）。該有效深度（例如金屬層222之頂 面到剛表面207之距離）可被選擇使得大部分被金屬層222 反射之光為紅色波長。 圖3 A-3D顯示一種形成一根據本發明之一實施例之影像 感應器之一成像像素300的方法。成像像素3〇〇為顯示於圖 1中之像㈣制5之至少-個像素的可行實施。顯示於圖 3A中之成像像素300之實施例包含—半導體層（即基板 305)、一保護氧化物310、一中間層電介質315，及一金屬 堆疊320。基板305係顯示a包含淺溝渠隔離ο )溝 渠、光電二極體325、一浮動擴散（「FD」）及—釘紫層 330。金屬堆疊320係顯示為包含金屬互連層⑷及犯、金 屬間電介質層340及345。ffi3A中亦顯示—傳送閘極说。 在圖3A所顯示之實施例中，光電二 、， 权植325係形成於基 板3 0 5内，並經組態以從前表面3 〇 7接#也 # ^ w 接收先。猎由可選之釘 糸層330，光電二極體325係顯示為— 门 奵糸先電二極體。在 一個實施例中’光電二極體325可為—▲ , ，l" 非釘紮光電二極體 或一部分釘紮光電二極體。此外， 先電二極體325可為任 何光敏元件，例如一光閘或光電容 奋此外，術語「像素」 140690.doc 201003905 在此旨在包含所有像素設計，包括CCD像素。 傳送閘極335亦被包含於成像像素3〇〇中，其經耦合以將 聚積於光電二極體325中的電荷傳送至浮動擴散？〇。在一 個實施例中，傳送閘極335為一種多結晶矽（即多晶矽）結 構。保護氧化物310及中間層電介質315被耦合至前表面 307。在一個實施例令，中間層電介質3$係氧化矽。 如圖3A所示，成像像素3〇〇包含金屬堆疊32〇。所顯示之 金屬堆疊320的實施例包含兩個金屬層河丨及河2，其被金屬 間電介質層340及345分隔。雖然圖从顯示—種兩層金屬堆 疊’金屬堆疊320亦可包含更多或更少的金屬層，以便在 基板305之前表面3〇7之上按線路發送信號。在—個實施例 中孟屬互連層Ml及M2為一種諸如铭、銅之金屬或不同 $屬的合金。在一個實施例中’金屬互連層⑷及奶藉由 濺鍍、準直濺鍍、低壓濺鍍、反應性濺鍍、電鍍、化學氣 相沈積或蒸鑛之方式而形成。在一個實施例中，傳送閘極 奶及洋動擴散骑由—洞、通孔或其他貫穿保護氧化物 及中間層電介質315的連接方式(未顯示)而被電耗合至 金屬互連層MUM2之-或多者。在一個實施例中，一鈍 化層（未顯不）被配置於金屬堆疊320之上。 參考請，於背面309執行—蝴植入。在一個實施例 ’石朋植人可利用氟化_F2)作為摻雜劑或利用乙侧烧 )作為摻雜劑源而執行。成像像素3(H)之改盖性能可 源自硼離子350在大約3xl〇u齙工/ 2 雔子/cm到5χ1015離子/cm2之 範圍内的劑量範圍。成像像素3〇〇之進—步的改善性能可 140690.doc -10- 201003905 源自硼離子350在大約1 Χίο丨4離子卜1〇丨5離子化瓜2之 範圍内的劑量範圍。 參考圖3C，其顯示所獲得的硼植入層355。在—個實施 例中，從背面309測量，植入深度360在大約1〇〇 nn^4〇〇Received. As noted above, the remaining substrate thickness 213 can also be selected such that the metal layer 222 is used to primarily reflect red (and longer) wavelengths of light (eg, photons reflected by the metal layer 222 over 5 〇 0 / 具有 have a red color or Long wavelength). Thus, the sensitivity of the pixel to the red (or longer) wavelength of light can be improved by providing a metal layer 222 that reflects a longer wavelength back to the front surface 207, an additional electron hole pair It can be generated here (N-region 21〇 can capture the released electrons). The effective depth (e.g., the distance from the top surface of the metal layer 222 to the surface 207) can be selected such that most of the light reflected by the metal layer 222 is a red wavelength. 3A-3D illustrate a method of forming an imaging pixel 300 of one of the image sensors in accordance with an embodiment of the present invention. The imaging pixel 3A is a possible implementation of at least one pixel of the image (4) shown in Fig. 1. The embodiment of imaging pixel 300 shown in Figure 3A includes a semiconductor layer (i.e., substrate 305), a protective oxide 310, an intermediate layer dielectric 315, and a metal stack 320. Substrate 305 shows that a includes shallow trench isolation, a trench, a photodiode 325, a floating diffusion ("FD"), and a nail violet layer 330. The metal stack 320 is shown to include a metal interconnect layer (4) and inter- and inter-metal dielectric layers 340 and 345. Also shown in ffi3A is the transmission gate. In the embodiment shown in Figure 3A, Optoelectronics, TG 325 is formed in the substrate 305 and is configured to receive from the front surface 3 〇 7 and # ^ w. Hunting consists of an optional nail layer 330, and a photodiode 325 system is shown as a door-to-door diode. In one embodiment, the photodiode 325 can be a -▲, , l" non-pinned photodiode or a portion of a pinned photodiode. In addition, the first diode 325 can be any photosensitive element, such as a shutter or photocapacitor. The term "pixel" 140690.doc 201003905 is intended to encompass all pixel designs, including CCD pixels. Transmit gate 335 is also included in imaging pixel 3, which is coupled to transfer charge accumulated in photodiode 325 to floating diffusion. Hey. In one embodiment, transfer gate 335 is a polycrystalline germanium (i.e., polysilicon) structure. Protective oxide 310 and interlayer dielectric 315 are coupled to front surface 307. In one embodiment, the interlayer dielectric 3$ is yttrium oxide. As shown in FIG. 3A, the imaging pixel 3A includes a metal stack 32A. The illustrated embodiment of metal stack 320 includes two metal layers, a river channel and a river 2, separated by inter-metal dielectric layers 340 and 345. Although the figure shows that the two-layer metal stack' metal stack 320 may also contain more or fewer metal layers to route signals over the front surface 〇7 of the substrate 305. In one embodiment, the Meng interconnect layers M1 and M2 are an alloy such as a metal such as a metal, or a metal of a different genus. In one embodiment, the metal interconnect layer (4) and milk are formed by sputtering, collimated sputtering, low pressure sputtering, reactive sputtering, electroplating, chemical vapor deposition, or steaming. In one embodiment, the transfer gate milk and the oceanic diffusion ride are electrically depleted to the metal interconnect layer MUM2 by a hole, via, or other connection through the protective oxide and interlayer dielectric 315 (not shown). - or more. In one embodiment, a passivation layer (not shown) is disposed over metal stack 320. For reference, perform on the back 309 - butterfly implant. This can be performed in one embodiment, 'Shi Pengzhi can use fluorinated _F2 as a dopant or B side burned as a dopant source. The masking performance of the imaging pixel 3 (H) can be derived from a dose range of boron ions 350 in the range of about 3 x 1 〇u / 2 雔 / cm to 5 χ 1015 ions / cm 2 . The improved performance of the imaging pixel 3 140 140690.doc -10- 201003905 is derived from the range of doses of boron ion 350 in the range of about 1 Χίο丨4 ion 〇丨1〇丨5 ionized melon 2. Referring to Figure 3C, the boron implant layer 355 obtained is shown. In one embodiment, measured from the back side 309, the implant depth 360 is approximately 1 〇〇 nn^4〇〇
麵的範心。在-個實施射，剩餘基板厚度如可具有 較佳值以大體反射光的紅色波長（例如，使得大部分被反 射之光為紅色波長或更長波長）。舉例來說，對於一個US 微米之像素，剩餘基板厚度365可為大約3微米。 士圖3D所頒示，一金屬層370被形成於背面3〇9上。一可選 的杉色濾光片3 8〇可被形成於該金屬堆疊之上。例如，一用 於檢測紅色波長的像素可包含—為紅色的彩色遽光片38〇。 圖4為-顯示根據本發明之-實_之前照式成像毕列 中兩個4電晶體（「4T」）像素之像素電路系統彻的電路 圖。像素電路系統400為一種用於實施圖丨之像素牵列 ⑽、11 2之像素2〇〇或圖3D之像素3〇〇中之各個像素的可行 像素電路I統構造。然而，應理解本發明之實施例不限於 4T像素構造；3T設計、取計及多種其他像素構造亦可 在圖4中，像素Pa及Pb被配置於兩個列及—個行中。各 個像素電路系統400之被顯示的實施例包含— PD、一傳送電晶體T1、—重 里《又电日日體丄2、一滿代拔‘ r Γ op /原極隨動 (SF」)電晶體T3及一選擇電晶體以。在操作時，傳送電 收-傳送信號ΤΧ，其將積聚於光電二極體阳中 勺包何傳送至一浮動擴散節點FD。 140690.doc -11 - 201003905 重設電晶體T2被福合於一電軌獅及該浮動擴散節點 扣之間以在-重設信號RST的控制下重設（例如將該㈣ 電或充電至-預設錢）。該浮動擴散節舒〇被輕合至^ 電晶體T3之閘極。SF電晶體T3㈣合於該電執vdd及選 ，電晶體T4之間。SF電晶體乃作為—從浮動擴散節酬 提供一高阻抗輸出的源極隨動胃而操作。最後，選擇電晶 體T4在-選擇信號SEL控制下選擇性地將像素電路系統 400之輸出耦合至讀出行線'' ^ ^ 在個貫施例中，該TX信 號、RST信號及SEL信號被控制電路系統12〇產生。該灯 L號、RST##。、SEL信號、VDD及地線可藉由金屬互連 層Ml及M2之方式而被定線於像素電路系統_中。在一個 實施例中，電晶體了 動擴散節點F D可如圖4所示藉由金屬互連層M丨及M 2之方 式而被連接。 本發明之上述實施例，包含發明摘要所描述之内容不具 有排他性或將本發明限制為被揭示之精確形式。雖然本發 明之具體實施例及實例為說明性之目的而被描述於此，但 相關技術熟練者將理解本發明範圍中的多種修改係可行 的。 鑒於如上之詳細描述，可對本發明做出這些修改。使用 於如下請求項中的術語不應被解釋為將本發明限制為揭示 於此3兒明書中的具體實施例。相反，本發明之範圍完全由 下之明求項界疋，其根據請求項解釋之既定原則而被理 解。 140690.doc -12- 201003905 【圖式簡單說明】 圖1為一種根據本發明之一者 圖。 & w的影像感應器之一方 圖2為—種根據本發明之— 之一成像像素的截面圖。 Λ施例的前照式影像感應器 實施例之前照式 圖3A-3D顯示一種形成根據本發明之 影像感應器之一成像像素的方法。The face of the face. In the case of a shot, the remaining substrate thickness is, for example, a red wavelength which can have a preferred value to reflect light substantially (e.g., such that most of the reflected light is a red wavelength or a longer wavelength). For example, for a US micron pixel, the remaining substrate thickness 365 can be approximately 3 microns. As shown in FIG. 3D, a metal layer 370 is formed on the back surface 3〇9. An optional sapphire filter 38 can be formed over the metal stack. For example, a pixel for detecting a red wavelength may comprise a red color magnifier 38". Fig. 4 is a circuit diagram showing the pixel circuit system of two 4-transistor ("4T") pixels in a real-time imaging array according to the present invention. The pixel circuit system 400 is a possible pixel circuit configuration for implementing each of the pixels of the pixel (10), 11 2, or the pixel 3 of FIG. 3D. However, it should be understood that embodiments of the present invention are not limited to 4T pixel construction; 3T design, fetching, and various other pixel configurations. In Figure 4, pixels Pa and Pb are arranged in two columns and in one row. The illustrated embodiment of each pixel circuit system 400 includes - PD, a transfer transistor T1, - a "return", a full-scale pull-up r r Γ op / original-pole follow-up (SF) Crystal T3 and a selective transistor. In operation, a transfer-transmission signal ΤΧ is transmitted which is accumulated in the photodiode sump and transferred to a floating diffusion node FD. 140690.doc -11 - 201003905 Reset transistor T2 is used to be reconciled between a rail lion and the floating diffusion node buckle under the control of the reset signal RST (for example, to charge (4) or charge to - Default money). The floating diffusion section is lightly coupled to the gate of the transistor T3. The SF transistor T3 (4) is combined between the electric volts vdd and the selected transistor T4. The SF transistor acts as a source that follows the source of the high-impedance output from the floating diffusion. Finally, the select transistor T4 selectively couples the output of the pixel circuitry 400 to the readout row line under the control of the select signal SEL. ^ ^ In the example, the TX signal, the RST signal, and the SEL signal are controlled. Circuitry 12 is generated. The lamp L number, RST##. The SEL signal, VDD, and ground can be routed in the pixel circuitry _ by means of the metal interconnect layers M1 and M2. In one embodiment, the transistor diffusion node F D can be connected by means of metal interconnect layers M and M 2 as shown in FIG. The above-described embodiments of the present invention, which are included in the summary of the invention, are not intended to be exhaustive or to limit the invention to the precise form disclosed. While the embodiments and examples of the invention have been described herein for illustrative purposes, those skilled in the art will understand that many modifications are possible in the scope of the invention. These modifications can be made to the invention in light of the above detailed description. The terms used in the following claims should not be construed as limiting the invention to the specific embodiments disclosed herein. Rather, the scope of the invention is to be understood by the following claims 140690.doc -12- 201003905 [Simplified illustration of the drawings] Fig. 1 is a diagram of one of the figures according to the present invention. One of the image sensors of & w is a cross-sectional view of an imaging pixel according to the present invention. Front-illuminated image sensor of an embodiment Example prior to use Figures 3A-3D show a method of forming an imaged pixel of one of the image sensors in accordance with the present invention.
圖4為一顯示根據本發明之一每 中兩個4電晶體（「4了」）像素之:之心式成像陣列 【主要元件符號_】 *講的電路圖。 100 影像感應器 110 讀出電路系統 115 功能邏輯 120 控制電路系统 200 成像像素 205 P型基板 207 前表面 209 背面 210 N_區域 211 植入深度 213 剩餘基板厚度 215 金屬深度 220 P +植入層 222 金屬層 140690.doc •13- 201003905 225 淺溝渠隔離 230 傳送閘極 235 Ν+區域 300 成像像素 305 基板 307 前表面 309 背面 3 10 保護氧化物 315 中間層電介質 320 金屬堆疊 325 光電二極體 330 釘紮層 340 金屬間電介質層 345 金屬間電介質層 350 硼離子 355 硼植入層 360 植入深度 365 剩餘基板厚度 370 金屬層 380 彩色濾光片 400 像素電路糸統 ΤΙ 傳送電晶體 Τ2 重設電晶體 Τ3 源極隨動電晶體 Τ4 選擇電晶體 140690.doc 14-Fig. 4 is a circuit diagram showing a heart-shaped imaging array of [the main component symbol _] * for each of two 4-cell ("4") pixels in accordance with one embodiment of the present invention. 100 image sensor 110 readout circuitry 115 function logic 120 control circuitry 200 imaging pixel 205 P-type substrate 207 front surface 209 back 210 N_region 211 implant depth 213 residual substrate thickness 215 metal depth 220 P + implant layer 222 Metal layer 140690.doc •13- 201003905 225 shallow trench isolation 230 transfer gate 235 Ν+region 300 imaging pixel 305 substrate 307 front surface 309 back 3 10 protective oxide 315 interlayer dielectric 320 metal stack 325 photodiode 330 pin Tie 340 Intermetal dielectric layer 345 Intermetal dielectric layer 350 Boron ion 355 Boron implant layer 360 Implant depth 365 Remaining substrate thickness 370 Metal layer 380 Color filter 400 Pixel circuit ΤΙ Transfer transistor Τ 2 Reset transistor Τ3 source follower transistor Τ4 select transistor 140690.doc 14-